Blender ( in my opinion) is as good as any commercial 3D software with many advantages due to it being an open source software with free commercial liscence. Being open source also means there are tons of add-ons for it that make life easier and funner.

There is an export/import addon for the SMD format which you will need to export your model as ( also exists for maya and 3ds max) and after export you need to create a qc file and convert the UV textures to VTF format (Valve Texture File). There are a few tutorials for Blender on how to do it, but for fully rigged character models, you will need to do some research on the Valve Developer wiki. Good luck, we're here if you have further questions.

Learn it. Its worth it. took me generally 2 month of following this tutorial: http://en.wikibooks.org/wiki/Blender_3D:_Noob_to_Pro (which quite some of is outdated, but it only challeneged me to figure things out myself) and a few tutorials here and there depending on what I wanted to do.Its not soo hard really, its just time consuming ( not boring though, lots of fun!)